const todos = {
    life:["eat","poop","drink","sleep"],
    work:["coding","banzhuaning","drawing","selling"],

    [Symbol.iterator]:function(){
        const all = [...this.life,...this.work]
        let index = 0
        return {
            next:function(){
                return {
                    value: all[index],
                    done: index++>=all.length
                }
            }
        }
    }
}
for (const item of todos){
    console.log(item)
}
